Colorado Corky, Bolduc, and the other Rs running have zero chance against Shaheen. And the fact that Ayotte lost to the comparatively less established Maggie Hassan in a year where Donald Trump won the EC and came very close to winning NH says a lot, especially when Trump's approvals in NH are abysmal and Shaheen is one of the most well-known political figures in the state right now.
This is why PVI can be misleading. NH pretty clearly has a strong/stubborn Democratic lean, but Democratic trends + lopsided margins in TX/CA/NY/IL/NJ/etc. make it appear more competitive than it actually is. Treating it as a hyper-competitive 50-50 state is pretty silly.